Factors Affecting Comfort in Summer - Refrigerant Charging Machine

In summer, the use of air conditioning cooling is essential, so a good refrigerant charging machine is a key factor in determining summer comfort. Before adding refrigerant to the car air conditioning, first evacuate for 1 hour. When the system has no leaks and is under vacuum, open the R134a bottle with the nozzle facing down, loosen the soft hose connector in the middle of the pressure gauge to release the air in the hose, and open the high-pressure side manual valve to inject liquid refrigerant from the high-pressure side.

How to correctly detect insufficient refrigerant

The weighing and charging method is the truly correct method, applicable to any refrigeration system. The method involves weighing the amount of refrigerant to be charged, and what needs to be done is to find out the amount or range of refrigerant to be charged from the relevant data. This is not just an observation method, but a real charging method. As long as the manufacturer specifies the correct charging amount on the nameplate for water-cooled cabinets or split units, weighing and charging can be done using a beam scale, electronic scale, dial scale, or other weighing devices after completely drying and evacuating the system. This charging method is the most suitable. For a system with some refrigerant, there are two methods to charge the refrigerant. 1. Release the already charged Freon, re-evacuate, and weigh for charging; Many maintenance personnel are reluctant to spend time recovering the refrigerant from a system that is undercharged before recharging. In this case, the following alternative method can be used. However, this is a comprehensive application of all the methods mentioned earlier or one or two of them. Note: Before using these methods, ensure that all coils are clean and that the airflow is correct. 2. Use the following method to continue adding refrigerant, measuring and recording all data. A. Charge while simultaneously checking superheat and subcooling. For air-cooled direct expansion systems, set the subcooling to 8~12°C and superheat to 7~8°C. B. Check the temperature difference between the inlet and outlet air of the coil. Ensure that the airflow of the condenser and evaporator is correct, as well as under moderate load conditions. C. Check and compare the suction/discharge pressures. Look for standard data provided by the manufacturer in the installation, operation, and maintenance manual. D. If there is a sight glass, check for bubbles in the sight glass. If there are bubbles, confirm whether they are due to excessive pressure loss or insufficient refrigerant. E. Check the compressor current. If the current is too low, analyze the reasons for the low current under several types of operating conditions of the system.

Detecting an error method for insufficient refrigerant

Everyone has a different perception of hot and cold. If your hands have calluses, then the temperature you perceive will be higher than the actual temperature. Generally, the human body feels temperatures above 37°C as hot and below 37°C as cool.

What is refrigerant charging

Principle: The refrigerant absorbs the heat from the cooled medium (such as water or air) and vaporizes in the evaporator, then transfers the heat to the surrounding air or water and condenses in the condenser.

What should be noted when charging refrigerant

Refrigerant is the core medium of the refrigeration system. Whether the refrigerant is charged correctly is related to the normal operation of the refrigeration system. Therefore, it is necessary to use the correct refrigerant charging method and pay attention to some matters. The precautions for refrigerant charging are:

Air conditioning equipment charging with Freon

Notes: If the air conditioning is powered off for more than 12 hours: When starting the air conditioning, the crankcase heater must be powered on for preheating first. The preheating time should be no less than 1 hour for every kilogram of refrigerant charged into the system. The purpose is to evaporate the liquid refrigerant mixed in the refrigerating oil in the crankcase, to avoid the compressor from sucking in liquid refrigerant, which can cause hydraulic compression.